A primary difficulty in treating diseases of the eye is introducing drugs or therapeutic agents into the eye and maintaining these drugs or agents at a therapeutically effective concentration in the eye for the necessary duration of a treatment. Systemic administration may not be an ideal solution because, often, unacceptably high levels of systemic dosing are needed to achieve effective intraocular concentrations, which increases the incidence of unacceptable side effects of the drugs. Simple ocular instillation or application is not an acceptable alternative in many cases, because the drug may be quickly washed out by tear-action or pass from the eye into the general circulation. Suprachoroidal injections of drug solutions have also been performed, but again, the drug availability is short-lived. Such methods make it difficult to maintain therapeutic levels of a drug in the eye for adequate time periods.
Efforts to address this problem have led to the development of drug delivery devices, or implants, which can be implanted into the eye such that a controlled amount of a desired drug can be released constantly over a period of several days, or weeks, or even months. Many such devices have been reported. But efficient, reliable injection with an acceptable level of patient discomfort can still be difficult to achieve.
A more facile, convenient, less invasive, and/or less traumatic means for delivering implants into the eye would be desirable.